Britain's FTSE bolstered by rallying banks

LONDON, Jan 13 (Reuters) - Britain's FTSE 100 share index edged up towards two-month highs on Monday, supported by a rally in heavyweight financials after regulators agreed to ease a new rule on how banks' leverage ratios are calculated.

The regulators agreed on Sunday that banks will be able to include derivatives on a net rather than the much bigger gross basis when calculating leverage ratios under Basel III.

The easing should help keep the global economy financed as it means banks will not have an incentive to ditch some types of assets, such as loans to companies, in order to meet the leverage targets.

Financials - which are the second biggest sector in the FTSE 100 - added 9.38 points to Britain's blue-chip share index.

"It's all about the banks. The relaxing of the regulations is really improving investor sentiment in the sector," said Jonathan Roy, a broker at London Stone Securities.

Barclays rose 2.2 percent, Royal Bank of Scotland was up 1.8 percent and Lloyds up 1.7 percent.

"This change in guidance around the leverage ratio calculation is likely to be most beneficial for investment banks, in our view, and hence of the quoted UK banks we would expect Barclays' shares to react most positively to this news," Gary Greenwood, analyst at Shore Capital, said in a note.

The FTSE 100 was up 7.70 points, or 0.1 percent, at 6,747.64 points by 0835 GMT, edging back towards a two-month intra-day high of 6,769.94 points hit on Friday.

Wm Morrison rose 3.7 percent after media reports that, following weaker than expected Christmas sales, the grocer was under pressure from shareholders to sell off some of its property portfolio.

Broader gains were capped by weakness in the FTSE 100's biggest sector - energy - as crude prices fell after an international deal on Iran's nuclear programme. The deal could eventually pave the way for a lifting of sanctions, bringing Iranian oil back onto the global market.

Oil major BP was down 0.6 percent, also impacted buy a target price cut from analysts at Barclays.